This invention relates to a vehicle and more particularly to a vehicle such as a motorcycle in which all wheels are driven.
As is well known in many types of vehicles, only the wheels at one end of the vehicle are driven. With a motorcycle, the rear wheel is normally driven and the dirigible front wheel is not driven. There are times, however, where it is desirable to also drive the front wheel of a motorcycle. However, because of the unique arrangement for the front wheel steering and suspension, conventional transmission systems do not lend themselves to application to conventional type of motorcycles.
There have been proposed, therefore, motorcycle front wheel drives wherein a hydrostatic transmission is employed. This hydrostatic transmission is comprised of a pump driven by the engine and a hydrostatic motor which drives the front wheel through a gearing arrangement. In one type of arrangement which has been proposed, the hydrostatic motor is disposed on one side of the wheel and drives the wheel through a gear transmission. This places the motor in an exposed location where it is likely to be damaged. Furthermore, the exposed positioning for the motor also puts the hydraulic lines in a position where they also could be damaged. In addition the side to side balance of the motorcycle will become unbalanced.
With another type of arrangement, the hydrostatic motor is actually nested within the hub of the front wheel. This avoids some of the aforenoted problems but introduces problems of its own. For example, with this type of arrangement, the front fork assembly and front wheel must all be specially manufactured for this purpose. Thus, this type of system cannot be easily adapted to existing motorcycles.
It is, therefore, a principal object of this invention to provide an improved and simplified driving arrangement for a dirigible front wheel of a vehicle such as a motorcycle.
It is a further object of this invention to provide an improved and compact hydrostatic motor, front wheel drive arrangement for a motorcycle.
It is yet further object of this invention to provide a compact motor, transmission arrangement for driving a motorcycle front wheel wherein the front wheel can be relatively conventional in construction and the front fork need not be specially adapted for the hydrostatic drive.